Jetpack 4.6 for jetson nx not booting up

i have jetson xavier nx and i flashed jetpack version 4.6 .thereafter something like this is displayed on monitor

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This is not a photo that should happen on Jetpack4.6. It is a jetpack5 boot screen.

How did you flash your board? Please use sdkmanager to flash.

i uploaded the image on sd card using balena etcher and then used that sd card for boot up

sdcard image won’t work. Please reflash system by using sdkmanager.

Your sdcard image can only work after sdkmanager update the bootloader back to jetpack4 bootloader.

i installed sdk manager in ubuntu 24.04 but it is not detect board . i have used usb cable for connection . I want to know if i am doing anything wrong

Jetpack4 can only get flashed by using ubuntu 18.04 host otherwise sdkmanager won’t let you download the BSP package.